librbd: disallow creation of v1 image format

qa/workunits/rbd/cli_generic.sh

@@ -1,5 +1,7 @@
 #!/bin/sh -ex
 
+export RBD_FORCE_ALLOW_V1=1
+
 # make sure rbd pool is EMPTY.. this is a test script!!
 rbd ls | wc -l | grep -v '^0$' && echo "nonempty rbd pool, aborting!  run this script on an empty test cluster only." && exit 1
 

qa/workunits/rbd/image_read.sh

@@ -54,6 +54,8 @@ DEFAULT_OBJECT_ORDER=22
 MIN_OBJECT_ORDER=12	# technically 9, but the rbd CLI enforces 12
 MAX_OBJECT_ORDER=32
 
+RBD_FORCE_ALLOW_V1=1
+
 PROGNAME=$(basename $0)
 
 ORIGINAL=original-$$

qa/workunits/rbd/krbd_data_pool.sh

@@ -2,6 +2,8 @@
 
 set -ex
 
+export RBD_FORCE_ALLOW_V1=1
+
 function fill_image() {
     local spec=$1
 

qa/workunits/rbd/merge_diff.sh

@@ -1,6 +1,8 @@
 #!/usr/bin/env bash
 set -ex
 
+export RBD_FORCE_ALLOW_V1=1
+
 pool=rbd
 gen=$pool/gen
 out=$pool/out

src/librbd/internal.cc

@@ -869,6 +869,11 @@ bool compare_by_name(const child_info_t& c1, const child_info_t& c2)
     }
 
     if (old_format) {
+      if ( !getenv("RBD_FORCE_ALLOW_V1") ) {
+        lderr(cct) << "Format 1 image creation unsupported. " << dendl;
+        return -EINVAL;
+      }
+      lderr(cct) << "Forced V1 image creation. " << dendl;
       r = create_v1(io_ctx, image_name.c_str(), size, order);
     } else {
       ThreadPool *thread_pool;

src/test/librbd/test_main.cc

@@ -24,6 +24,8 @@ extern void register_test_operations();
 
 int main(int argc, char **argv)
 {
+  setenv("RBD_FORCE_ALLOW_V1","1",1);
+
   register_test_librbd();
 #ifdef TEST_LIBRBD_INTERNALS
   register_test_deep_copy();

src/test/pybind/test_rbd.py

@@ -37,6 +37,8 @@
 IMG_SIZE = 8 << 20 # 8 MiB
 IMG_ORDER = 22 # 4 MiB objects
 
+os.environ["RBD_FORCE_ALLOW_V1"] = "1"
+
 def setup_module():
     global rados
     rados = Rados(conffile='')